What is the cause of the rust manhole cover? In this case, how can we solve it? The details as below;
1. There are chloride ions in the use environment of the well cover: chloride ions are widespread, such as salt, sweat, sea water, etc. In the presence of chloride ions, corrosion is very fast, even more than ordinary low carbon steel. Therefore, the use environment of the well cover is required, and it needs to be wiped frequently to remove dust and keep clean and dry.
2. No solid solution treatment: alloy elements did not dissolve into the matrix, resulting in low alloy content in the matrix structure and poor corrosion resistance. So we should pay attention to the protection measures in this regard.
3. Manhole cover is naturally intergranular corrosion: this material without titanium and niobium tends to intergranular corrosion. The intergranular corrosion can be reduced by adding titanium and niobium together with stable treatment. A high alloy steel that can resist corrosion in air or in a chemical corrosive medium.
How to prevent the well cover from rusting is divided into two points:
1. Spray derusting: when removing rust, it is necessary to remove all rust and oxide on the surface of cast iron manhole cover. The power of air separated by oil and water is very great. The friction between the air and the manhole cover. The advantages of instant cleaning are no fixed place, high efficiency, large flexibility of spray point and no dead angle. It is convenient for the adhesion of paint. Prevent rusting again.
2. Rust removal by jetting: under the centrifugal action of high-speed rotation. Abrasive can clean the well cover with a large friction area. The advantages of this method are high efficiency, good derusting quality, and slight reduction of workers' high power. It is important that the air pollution is relatively low. Therefore, the general large-scale manufacturers use this method to remove rust.
No matter what kind of derusting method is used, it is dangerous to operate. Please improve your safety awareness and ensure your personal safety.